Implemented terrain chunk caching.

1 files changed, 90 insertions, 0 deletions

diff --git a/terrain_loader.cpp b/terrain_loader.cpp
new file mode 100644
index 0000000..d908aca
--- /dev/null
+++ b/terrain_loader.cpp
@@ -0,0 +1,90 @@
+#include "terrain_loader.h"
+
+#include <noise/noise.h>
+#include "noiseutils/noiseutils.h"
+#include <boost/format.hpp>
+#include <boost/filesystem/fstream.hpp>
+
+using namespace noise;
+
+TerrainLoader::TerrainLoader(int seed, fs::path root) {
+	this->seed = seed;
+	this->root = root;
+}
+
+TerrainLoader::~TerrainLoader() {
+}
+
+float *TerrainLoader::generate_heights(int x, int y, int width, int height) {
+	module::Perlin mod;
+	mod.SetSeed(seed);
+
+	utils::NoiseMap heightmap;
+	utils::NoiseMapBuilderPlane heightmap_builder;
+
+	heightmap_builder.SetSourceModule(mod);
+	heightmap_builder.SetDestNoiseMap(heightmap);
+
+	heightmap_builder.SetDestSize(width, height);
+	heightmap_builder.SetBounds((double)x / 100, (double)(x+width) / 100, (double)y / 100, (double)(y+height) / 100);
+	heightmap_builder.Build();
+
+	float *heights = new float[width*height];
+	for(int i = 0; i < width; i++) {
+		for(int j = 0; j < height; j++) {
+			heights[i*height + j] = 10*(1+heightmap.GetValue(i, j));
+		}
+	}
+
+	save_chunk(heights, x, y, width, height);
+
+	return heights;
+}
+
+float *TerrainLoader::get_chunk(int x, int y, int width, int height) {
+	float *h;
+	if(has_chunk(x, y))
+		h = load_chunk(x, y, width, height);
+	else
+		h = generate_heights(x, y, width, height);
+	return h;
+}
+
+bool TerrainLoader::has_chunk(int x, int y) {
+	return fs::exists(root / (boost::format("%d.%d.chunk") % x % y).str());
+}
+
+void TerrainLoader::save_chunk(float *chunk, int x, int y, int width, int height) {
+	fs::path p = root / (boost::format("%d.%d.chunk") % x % y).str();
+	fs::ofstream os(p);
+
+	os << width << std::endl;
+	os << height << std::endl;
+
+	for(int x = 0; x < width; x++)
+		for(int y = 0; y < height; y++)
+			os << chunk[x*height + y] << std::endl;
+	os.close();
+}
+
+// NOTE: assumes width <= chunk_size+1, likewise for height
+float *TerrainLoader::load_chunk(int x, int y, int width, int height) {
+	fs::path p = root / (boost::format("%d.%d.chunk") % x % y).str();
+	fs::ifstream is(p);
+
+	int w, h;
+	is >> w;
+	is >> h;
+
+	float *chunk = new float[width*height];
+	for(int x = 0; x < w; x++)
+		for(int y = 0; y < h; y++) {
+			float v;
+			is >> v;
+			if(x < width && y < height)
+				chunk[x*height + y] = v;
+		}
+	is.close();
+
+	return chunk;
+}